The present invention relates to containers for liquids, such as a drink mug. More particularly, it relates to a mug which will tend to maintain the contents hot or cold, permit the user to drink from the mug, and reduce the likelihood of splashing.
Double wall containers, such as vacuum bottles and the like, have been used for maintaining the temperature of the contents. Such devices are relatively expensive, and are not handy for drinking and hence are seldom used by a drink consumer.
A variety of glasses, cups and mugs, herein all referred to as mugs, are widely used by the drinker, typically with the mug being filled or refilled from a vacuum bottle or other source of hot or cold liquid.
More recently, mugs with removable lids for reducing temperature change of the contents while at the same time providing for retaining the liquid should the mug be tipped and for drinking from the mug without removing the lid have been developed. Two such products are shown in U.S. Pat. Nos. 4,582,218 and 5,018,636.
In the mug of the U.S. Pat. No. 4,582,218 patent, a cylindrical portion 46 of the lid slides into a mating sidewall portion of the mug to engage a shelf 30. The lid is locked in place by mating keys 48, 50 and gaps 52, 54, with a friction seal 60 at the upper end of the lid, and with a handle 70 in the well 62 in the cylindrical portion of the lid. This prior design requires a rather complex structure, particularly for the lid, and was replaced by the design of U.S. Pat. No. 5,018,636 by the same patentee.
The later patent states that it is an improvement in the mug body design to facilitate ease of manufacture and an improvement in the top which provides better sealing and more efficient insertion and removal.
The later patent mug uses a continuous shelf 30, with a hemispherical body 50 and flexible spheres 54, 74 projecting downward from the lid for sealing engagement with the shelf. While this design is simpler than that of the earlier patent, it does not provide for positive restraint of the lid in the mug.
It is an object of the present invention to provide a new and improved drink mug with lid which is simple in construction and in operation and at the same time provides a positive interconnection between the lid and mug. Other objects, advantages, features and results will more fully appear in the course of the following description.